With "marker lines" I believe you mean the ticks
of Kendo UI Slider? It this is the case the most likely reason for the observed behavior is the number of the ticks
. By design if there are too many ticks such are removed. If this is not the case, I would like to ask you to send a runnable project that demonstrates your current implementation. This way I would be able to check what is going wrong and advice you further.
the Telerik team
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